As you may have heard from VMware, the end is near for their VMware Consolidated Backup product, or VCB. It has been superseded by a new technology called vStorage APIs for Data Protection, or VADP. See their posting at http://app.connect.vmware.com/e/es.aspx?s=524&e=12880125.
In NetBackup 6.5.1, we introduced "NetBackup for VMware" which requires VCB from VMware. The VCB requirement remains in all later NetBackup 6.5.x releases. There are no plans to support VADP in NetBackup 6.5.
In NetBackup 7, which is now available, we support both VCB and VADP. In fact, we support mixed environments of both, which recognizes that customers do not likely upgrade all ESX servers at once.
There is even more good news: you do not need to upgrade to "vSphere 4" to leverage VADP (but vSphere is...